_base_ = "./grid_rcnn_r50_fpn_gn-head_2x_coco.py"
model = dict(
    pretrained="open-mmlab://resnext101_32x4d",
    backbone=dict(
        type="ResNeXt",
        depth=101,
        groups=32,
        base_width=4,
        num_stages=4,
        out_indices=(0, 1, 2, 3),
        frozen_stages=1,
        style="pytorch",
    ),
)
# optimizer
optimizer = dict(type="SGD", lr=0.02, momentum=0.9, weight_decay=0.0001)
optimizer_config = dict(grad_clip=None)
# learning policy
lr_config = dict(
    policy="step",
    warmup="linear",
    warmup_iters=3665,
    warmup_ratio=1.0 / 80,
    step=[17, 23],
)
runner = dict(type="EpochBasedRunner", max_epochs=25)
